Engine starter gearing



Y. SEKELLA 2,304,284

ENGINE STARTER GEARING Dec. 8, 1942.

Filed Aug. 12, 1941 M Q INVENTOR gm ion, 6' g W BY E Patented Dec. 8, 1942 ENGINE. STARTERJGEARING Youston Sekella, Elmira Heights,.N. Y., assignori V ,1. w

to Bendix Aviation Corporation; .South; Bend, Ind., a corporation of Delaware,

Application August 12, 1941; Serial No.-4 6, 493" v Claims.

The present invention relates to engine starter gearing and more particularly to a novel arrangement for controlling thetraversal of a starter pinion into mesh with an engine gear.

It is an object of the present invention to provide a novel starter gear which is efficient in operation and simple and economical in construction.

It is another object to provide such a device having a novel arrangement for preventing the starter pinion from drifting into engagement with the engine gear.

It is a further object to provide such a device including a nut for traversing the pinion, and a barrel member for enclosing the nut and connecting it to the pinion.

It is another object to provide such a device in which a member for connecting the nut and barrel is further adapted to perform the function of an anti-drift means for the pinion.

It is another object to provide such a device in which the anti-drift means is arranged to be rendered inoperative by centrifugal force when the barrel and its associated parts are rotating above a predetermined speed.

Further objects and advantages will be apparent from the following description taken in connection with the accompanying drawing, in which:

Fig. 1 is a side elevation partly broken away and in section showing a preferred embodiment of the invention;

Fig. 2 is a section taken substantially on the line 22 of Fig. 1; and

Fig. 3 is a View similar to Fig. 2 showing the parts in overrunning condition.

In Fig. l of the drawing there is illustrated a power shaft 1 which may be the extended armature shaft of a starting motor not shown. Shaft I has a smooth reduced bearing portion 2 providing a stop shoulder 3, and a further reduced portion 4 on which a screw shaft 5 is fixed in any suitable manner as by means of a cross pin 6.

The outer surface of the screw shaft 5 is flush with the bearing portion 2 of the power shaft, and a pinion 1 is slidably journalled on the screw shart and said bearing portion for longitudinal movement into engagement with a member such as a gear 8 of an engine to be started.

Means for traversing the pinion I is provided in the form of a nut 9 on the screw shaft having a radial flange l I and a barrel member l2 surrounding the nut and extending over a flange l3 fixed to the pinion I. A block M of elastically deformable material lsuchas rubber is mounted on the nut 9"within the'barrel and is maintained under slight initial. compression by meansof a lip l5 on the barrel engaging thepinion flange l3, and a. spring lock ring l'fi in the open end of the barrelengaging the flange of the nut.

vAccording to the,.present. invention the .lock ring I6 is adaptedtd'furiction' as, an .anti-drift means for the pinionby' yieldinglyiresistingrlongitudinal movement of the barrel I2 fromidle position. For this purpose the screw shaft 5 is provided with a circumferential groove I1 forming an inclined shoulder l8 and one end of the lock ring 16 is bent inwardly in the form of a loop l9 (Fig. 2) arranged to engage yieldingly with the shoulder 18 when the parts are in idle position. Preferably the loop is arranged in close proximity to the other end of the ring as shown in Fig. 2 so as to form a lock to prevent removal of the ring [6 as long as the parts are assembled on the screw shaft. When the screw shaft is removed however, the loop |9 forms a convenient means for readily removing the lock ring in order to disassemble the nut from the barrel and pinion.

In order to control the action of the anti-drift, and render it inoperative when the frictional effect thereof is not desired, the loop I9 is provided with an extension 20 of such length as to cause flexure of the loop by centrifugal force to relieve its frictional engagement with the screw shaft.

In operation, with the parts positioned as in Figs. 1 and 2, the frictional engagement of the loop I9 with the shoulder l8 of the screw shaft normally holds the pinion retracted. When the power shaft is rotated by energization of the starting motor, the rotational inertia of the nut and its associated parts causes the nut to overcome the effect of the anti-drift and traverse the pinion into mesh with the engine gear. When the pinion engages the shoulder 3 on the power shaft, the pinion is thereby connected to rotate with the power shaft and crank the engine, the connection being cushioned by the elastic member I4. When the engine starts, the acceleration of the pinion by the engine gear causes it to overrun the power shaft and thereby be returned to idle position. At the same time the rapid rotation of the parts causes the loop IQ of the antidrift to be flexed so as to disengage it from the screw shaft and thus render the anti-drift inoperative during the demeshing operation.

Although but one embodiment of the invention has been shown and described in detail, it will be pinion including a. barrel and a lock ring seated in the barrel and forming an abutment for they nut, said lock ring having an elastic extension adapted to bear frictionallyon the screw shaft.

2. In an engine starter drive-apower shaft, a pinion slidably journalled thereon, means for traversing the pinion including a screw shaft fixed to the power shaft, a flanged nut threaded on the screw shaft, means connecting the nut to the pinion including a barrel and a lock ring seated in the barrel engaging the flange of the nut, said lock ring having an extension adapted to bear frictionally'on the screw shaft to resist traversal of the pinion from idle position.

3. In an engine starter drive a power shaft having a. smooth bearing portion, a pinion slidably journalled on said bearing portion, and having a radial flange fixed thereto, a screw shaft fixedly connected to the power shaft, a nut on the screw shaft having a radial flange, a block of elasticallydeformable material between said flanges, a barrel enclosing the flanges and a lock ring confining the nut in the barrel and having a part frictionally engaging the screw shaft.

4. In an engine starter drive a power shaft having a smooth bearing portion, a pinion slidably journalled on said bearing portion, and having a radial flange fixed thereto, a screw shaft fixedly connected to the power shaft, having an inclined shoulder, a nut on the screw shaft having a radial flange, a block of elastically deformable'material between said flanges, a barrel enclosing the flanges, and a lock ring seated in the barrel confining the nut in the barrel and hav- I ing a part adapted to engage the shoulder to resist traversal of the barrel.

5. In an engine starter drive a. pinion sliclably mounted for movement into and out of engagement with a member of an engine to be started, means for traversing the pinion including a screw shaft and nut, a barrel connecting the nut and piniomand a spring ring confining the nut in the barrel, said ring having a, portion extending inwardly to frictionally engage the screw shaft and resist longitudinal movement of th barrel and pinion, said extension being so formed asto flex and relieve said frictional engagement responsive to centrifugal force.

- YOUSTON SEKELLA. 

